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Turbo TR6? Yes sir!

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rjtr6 Avatar
rjtr6 Richard Janvier
Quebec, Quebec, Canada   CAN
Hello Everybody
This is my first post and I'm french speaking so please be indulgent.

I want to share my experience in modifying my TR6 induction.
During the summer, my son and I installed a turbo on a US spec 1974 TR6 (CR 7.75).
Everything is reversible to stock and OEM intake and exhaust manifold were used.

We fabricated a J-pipe to connect the turbo to the manifold and prepared an aluminum intake extension
to connect it to the existing intake. This is a draw-thru set up, using ONE CD175 Zenith-Stromberg.
The turbo is a Garrett T3 (Super 60) with .60 intake side and .48 exhaust side. It spools very fast,
giving full boost around 2500 rpm. To avoid detonation, we use premium gas and the mechanical spark advance
was limited to 16 degrees at the distributor by adding a sleeve over the limiter pin. I also have an electronic ignition.
Air-fuel ratio was monitor with a wideband oxygen sensor and corrected by adjusting/changing the metering needle of the carb. At 7 psi of boost I use B1AR adjustable needle and it works fine. The next summer (yes there is snow up here) I plan to increase the boost to 8-10 psi and change the needle to B1R. I don't want to go higher than 10 psi to avoid damage to the rest of the driveline. Even at 7 psi, the car is a thrill to drive. Much more responsive than stock. 0 to 60 mph is around
6-6.5 sec. This is quite fast for a TR6!
I will post pictures very soon.

Best to all of you
Richard

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tmpass Avatar
tmpass Tim P
Medway, MA, USA   USA
1970 Triumph GT6+ (MkII) "Capo"
1970 Triumph GT6+ (MkII) "Blue Oxide"
In reply to # 924771 by rjtr6
I will post pictures very soon.

Yes because in all reality, this post is worthless without pictures.

rjtr6 Avatar
rjtr6 Richard Janvier
Quebec, Quebec, Canada   CAN
Here are few pictures of my set up.
I kept the stock intake and exhaust manifold as you can see.

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tr6bobnf Avatar
tr6bobnf Bob Evans
Paradise, Newfoundland, Canada   CAN
Richard:

Bienvenue - Welcome to the Forum. Unfortunate that your first response from this group was to indicate your post was useless so I'll take this opportunity to extend a welcome and compliment you on your modification. Nice work!

Cheers,



_________________________
Bob
1976 TR6 - CF53465U

Trboost Avatar
Trboost Mitch Seff
Ny, Oceanside, USA   USA
Nice work. It's amazing how empty the engine bay looks. Turbo'd TR's are rare. The most notable and knowledgable guy I know is Dick Taylor . If my memory is correct, he has been running an original kit designed by Kastner using a Rajay turbo for many years with remarkable results. His car is proof that with proper tuning this power adder makes for a reliable and really fast ride. Keep posting your progress.



Mitch Seff
Oceanside N.Y.
75 TR6 Supercharged

tmpass Avatar
tmpass Tim P
Medway, MA, USA   USA
1970 Triumph GT6+ (MkII) "Capo"
1970 Triumph GT6+ (MkII) "Blue Oxide"
In reply to # 924926 by tr6bobnf Richard:

Bienvenue - Welcome to the Forum. Unfortunate that your first response from this group was to indicate your post was useless so I'll take this opportunity to extend a welcome and compliment you on your modification. Nice work!

Cheers,

In the words of Sergeant Hulka, "Lighten up Francis!" I was expressing interest in standard forum banter.... I wanted to see the setup.

Thanks for the pictures looks like a robust setup, I always wondered about fuel delivery on these setups, and clearances in the engine bay exhaust routing.... Did you weld up the intake pipes yourself? Nice work.

rjtr6 Avatar
rjtr6 Richard Janvier
Quebec, Quebec, Canada   CAN
Thank you for the welcome

Yes, I did this set up from scratch with my son. He is a better welder than me, so I let him do the aluminum welding.
I'm better with regular steel. The most difficult task was the design of the down pipe on exhaust side. The space is very
limited in this area, that's why I used a turbo with a separate wastegate (see pictures below). I also have to cover the starter with reflective blanket to protect it from the heat of the J-pipe. I even wrap the J-pipe for more protection.
The tuning was not so difficult. I downloaded a very useful needle comparator (in excel file)from internet. My main concern was the size of the carb. I was afraid that one of the stock Zenith-Stromberg was too small. It's not the case. The car accelerate eagerly to the redline. I think I will add a rev limiter to avoid over enthousiasm. Future improvements will be in the suspension/direction/brake department.

Best to all of you
Richard

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AJ6mod6 Avatar
AJ6mod6 Gareth T
Disabled Account, Antarctica   ATA
1989 Jaguar XJ40 "Animal2"
It has been done before and this was in fact the turbo used.

The 2.5L has a fatal flaw, if you want to run higher powers, you start to get high losses at higher revs, and you invariably run out of revs especially with a USA 3.7 diff and no overdrive.

The solution was to use the 2L based engine and run over 1 bar boost.

This with a well sorted head and exhaust knocked a good solid 260-280bhp with a lot more to come with Nitrous.
Just to give you some idea of the possibilities and the strength of the block.

In that case a fully fabricated 6 branch inlet was used with a fabricated 6 branch exhaust into the turbo.

It's also useful to look at water injection and a proper intercooler.

tr6bobnf Avatar
tr6bobnf Bob Evans
Paradise, Newfoundland, Canada   CAN
In reply to # 924930 by tmpass
In reply to # 924926 by tr6bobnf Richard:

Bienvenue - Welcome to the Forum. Unfortunate that your first response from this group was to indicate your post was useless so I'll take this opportunity to extend a welcome and compliment you on your modification. Nice work!

Cheers,

In the words of Sergeant Hulka, "Lighten up Francis!" I was expressing interest in standard forum banter.... I wanted to see the setup.

Thanks for the pictures looks like a robust setup, I always wondered about fuel delivery on these setups, and clearances in the engine bay exhaust routing.... Did you weld up the intake pipes yourself? Nice work.

Tim:
"Standard Forum banter" usually comes into play after a new member, who is not yet familiar with how we tend to go back and forth and occasionally take a good-natured jab at each other, has been introduced and welcomed to the forum. The new guy indicated he would be posting pictures very soon in his introductory post. I'm not familiar with Sgt. Hulka my friend, but as a response to a first post, yours quite frankly came across as rude - ya could've added a Smiley Face - 'nuff said.



_________________________
Bob
1976 TR6 - CF53465U

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rjtr6 Avatar
rjtr6 Richard Janvier
Quebec, Quebec, Canada   CAN
Yes, I know that the 2.5L engine is not for higher rpm.
That's the reason for the rev limiter.

Anyway, the cylinder head doesn't flow very well
in stock form, so it's useless to try to rev this engine.

I was not sure about adding this turbo
because I was afraid about turbo lag, but with the .48 trim on the exhaust side, the lag is not noticeable
and the boost is almost immediate.

At the beginning, this project was to add a little more power to an anemic and very low compression engine.
It becomes a father and son project and the final goal was not so important.

I'm pretty sure that, as you say, a 2L engine is a better choice to get high power but this is another level
of modifications well beyond I plan to reach: head modification, intake and exhaust fabrication, etc.
It takes an experimented person to modify the Triumph head and I'm not sure that I am this guy.

So next summer I will drive a little fun car with a big smile on my face and the feeling that I've done
something with my son that he will never forget. That's more than enough.

Cheers

dicta dick Taylor
Downey, Callifornia, USA   USA
Richard --- First off, it's good that you and your son found this to be a joint effort. I can suggest a few things you may want to add to your setup, somewhere down the road. Having 27 years of turbocharging a TR6 to draw from, this is some of what I found:

To help avoid detonation, after you get used to the present boost levels and want to take it higher, (this is addicting stuff).

a) Connect an MSD6-BTM ignition module. This unit has a feature that retards ignition advance depending on how much boost pressure is sensed. It can be adjusted remotely, as in the cockpit, if you choose. To set this up doesn't take much electrical savvy, to which I can attest! MSD gives a step-by-step instructions included in the kit, with all wires, etc. The big advantage of this is that one can set initial spark advance to where the engine is happy. No need to limit total advance with "fattening the limit post", as there could be times when, off-boost, you'll want this advance undeterred. The MSD will automatically retard spark when under boost conditions. This will save you some pistons!

b) Water injection - Again, not difficult to set up. It can be triggered by a simple pressure switch, like the one that senses oil pressure, to operate a pump. The three terminal one used for the later TR6 is a good one, and will turn on the pump when 4 lb. of pressure is sensed. An injection needle with approx. a .030 orifice aimed directly into the carburetor air stream works well. This jet of water gets pulverized upon meeting the compressor turbulence under boost and significantly cools down the charge. If the water reservoir is exposed to freezing conditions, then a 50/50 mix of water/alcohol can be used. An in-line water filter is recommended, to keep the needle free of contaminants.

c) You may find that the carburetor ices up when exposed to long highway runs. If you find that you must engage the choke when slowing down to idle speeds, this could be the reason - the fuel is entering the engine in heavy droplets. A water jacket between the carburetor and the turbo is one way to warm up the fuel. Note that you may not find this to be a problem with short runs around town.

I have found that the stock TR6 drive train is up to the task of handing about twice the power of the stock engine. If hammered on a lot in first gear, then one should look into upgrades, such as the Toyota 5 speed, and an LSD at the rear.

There's a lot more one can do for fast, safer driving, but the above should be a good continuing point!

Dick
342,000 miles, 200,000 with a turbo

rjtr6 Avatar
rjtr6 Richard Janvier
Quebec, Quebec, Canada   CAN
Dick,

Thank you for the suggestions. I'm glad to have the advice from someone who has experience with turbo.
As you said, it is very addictive to have such power under the foot smiling smiley

During the winter, I will install a water/methanol injection system. It is already on the bench.

Yes, it's a very good idea to get the MSD. It makes the ignition tweaking much more easy. Next buy!

I didn't noticed carb icing yet. Maybe because the intake between the carb and the compressor wheel is very short.
I also use a smaller carb than you do (1.75'' vs 2''). Maybe the droplets are smaller because of the higher velocity.
I take note of that issue and check this out on the next summer. Maybe more plumbing to do?!

The next step of improvement will be the suspension/steering/brake. I will post my progress.
I think about urethane bushes, new coil springs (stock or little stiffer) and better brakes (Cressida vented disc).
Gearbox and LSD diff are on a further step.

Thank you again for your advice

Richard

Punkdogstr6 Doug Lawson
Culver City, California, USA   USA
Welcome Richard and son.
It appears that you two are very good fabricators and engineers. Nice work guys.
I work on a lot of turbo charged light aircraft so I have a few question about your mod. Perhaps Dick could jump in here also.
On aircraft engines the turbo is always mounted before the fuel control. Most of the time we use mechanical fuel injection but there are systems using carburetors. Few work very well. Why did you guys decide to place the carb ahead of the turbo ?
I may have missed this but how are you controlling the turbo ? Did you use a fixed waste gate or some type of controller.
On aircraft we use inter coolers to drop the temp of the turbo output air ( what we refer to as upper deck pressure ) so why not that then a water injection system ? It's a lot less parts.
BTW, Your English is better than most who call it their native language.
D.

dicta dick Taylor
Downey, Callifornia, USA   USA
In reply to # 927110 by Punkdogstr6 Welcome Richard and son.
It appears that you two are very good fabricators and engineers. Nice work guys.
I work on a lot of turbo charged light aircraft so I have a few question about your mod. Perhaps Dick could jump in here also.
On aircraft engines the turbo is always mounted before the fuel control. Most of the time we use mechanical fuel injection but there are systems using carburetors. Few work very well. Why did you guys decide to place the carb ahead of the turbo ?
I may have missed this but how are you controlling the turbo ? Did you use a fixed waste gate or some type of controller.
On aircraft we use inter coolers to drop the temp of the turbo output air ( what we refer to as upper deck pressure ) so why not that then a water injection system ? It's a lot less parts.
BTW, Your English is better than most who call it their native language.
D.

Punkdog ---Dick, here. Rich and son may have their own reasons for having the carb before the turbo, but one of them could be the need for not having to"box in" the carburetor. Otherwise pressure from the turbo could cause its float to sink, as the pressure differential would be too great when on boost., it Not the case when using injectors.
So far as intercooling in place of water injection, we know that we don't want a mix of fuel and air going into/out of an intercooler. (Air only) It is true that an intercooler is certainly less fussy to maintain. With water as the cooling medium it must be checked upon occasionally to be sure it's working! (I have a red light in the cockpit to show when the pump is boost activated). Also the small nozzle for the water spray needs to be tested as to the stream of liquid coming out. This is easy to check by using a momentary switch, such as the one that's part of the TR6 windshield washer arrangement. For those interested in more details on the subject, I would recommend the book on TURBOCHARGERS, as written by Hugh MacInnes.

Punkdogstr6 Doug Lawson
Culver City, California, USA   USA
Hey guys,
I'm stuck on the sofa after leg surgeries so I have plenty of time to be a pest. Thought I'd pass along some aircraft turbo stuff.
On very large ( 1,000 plus hp ) radial engines with super chargers they would inject water into the fuel air mixture to increase take off power and help with cooling.
Since aircraft engines seldom turn more than 2,700 RPM they don't have variable timing to help prevent detonation.
What they did have was green 130 and purple 145 octane fuel. I had a Z/28 with 12:1 or more pistons that loved the 130 fuel that I bought at the local airport.
The purple 145 octane was mostly for military aircraft like a B29. Even with that the engines required constant cylinder replacement and had a nasty habit of blowing cylinders off the engine on take off. Take offs are usually made with full power depending on aircraft weight and runway length. When you're loaded with bombs and a thousand gallons of fuel a cylinder failure on take off made for tense ride. About all they could do was hope the aluminum engine would keep running and not catch on fire until they could dump the bombs to lighten the load then shut the engine down. I once saw a water tank from one of these planes and I would guess that it held at least 60 plus gallons. All used for one take off.
Crazy stuff but it worked due to high quality.

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